An ever-increasing concern exists today regarding high blood lipid levels experienced by over sixty million Americans, especially levels of cholesterol and triglycerides. A large body of evidence also indicates that improving dietary habits can reduce the risk or delay the onset of chronic diseases such as heart disease and stroke. Growing consumer demand for non-traditional foods and interest in self-medication are supporting markets for special food products at the same time that health care costs continue to exceed one trillion dollars annually. A priority for newly-designed foods must be to restore Omega-3 fatty acids (n-3) to human diets and also to balance the ratio of Omega-6 (n-6) fatty acids to n-3 fatty acids in human diets. Low-fat diets currently recommended for reducing total cholesterol and low-density lipoproteins (“LDL-cholesterol”) also increase plasma triglycerides and decrease high-density lipoproteins (“HDL-cholesterol”) concentrations, thus potentially increasing the risk of cardiovascular disease. Nutrition scientists are working to create and identify foods from plants with functional properties that have specific physiological and/or nutritional effects that improve health.
The present invention encompasses the process of reducing total plasma cholesterol and plasma LDL-cholesterol, while maintaining normal plasma triglyceride levels, and of increasing blood hematocrit and plasma HDL-cholesterol levels in humans with elevated blood lipid levels and in animals by the use of natural components of waterleaf (genus Talinum).
Talinum is a small genus of the purslane family (Portulacacae), which appears to possess a unique nutritional potential. Waterleaf is in the genus Talinum and the species triangulare and is a leafy vegetable found in West Africa, the West Indies, South America (Adams, et al., Flowering Plants of Jamaica, Pukl, University of West Indies, (1972)) and the warmer parts of the world (Mabberly, The Plant Book: A Portable Dictionary of Higher Plants, Cambridge University Press, Cambridge, Mass. (1990)). The leaves and tender stems of waterleaf are consumed as a vegetable or as the constituent of a sauce by the populations of the areas where it is grown. Waterleaf grows spontaneously during the growing season, and it is common in a variety of habitats including roadsides, open fields, and abandoned agricultural lands. Although it is extensively consumed in the diet of populations where it is abundant, not much is known about its nutritive value. Waterleaf's crude protein content compares favorably with that of cowpea, peanut, millet, and cashew nuts (Egwin, Composite Quality Cost Index (CQCI): A New Biochemical Rating System for Vegetable Food Protein, Nig. J. Sci. 13:323–329 (1979)). Akachuku and Fawusi (Growth Characteristics, Yield and Nutritional Value of Waterleaf, Talinum Triangulare (Jacq) Wild in a Semi-Wild Environment, Discovery and Innovation 7:163–172 (1995)) also reported crude protein content of waterleaf leaves and tender stems as high as 29.4% and 13.4%, respectively. Sridhar and Lakahminarayana (Lipid Classes, Fatty Acids, and Tocopherols of Leaves of Six Edible Plant Species, J. Agric. Food Chem 41:61–63 (1993)) reported high total lipids, essential oils, and alpha-tocopherols and beta-tocopherols in Talinum triangulare. 
A paucity of information exists on the health and nutritional benefits of waterleaf in humans and/or animals. Although purslane has been shown to possess nutritional qualities for reducing serum cholesterol and serum triglycerides in laboratory animals (U.S. Pat. No. 5,688,508), the present invention shows for the first time that waterleaf contains superior nutritional qualities that, when consumed by humans, vastly improves human health. Waterleaf contains a rich source of n-3 fatty acids and other nutrients that the present invention shows reduces harmful total plasma cholesterol and plasma LDL-cholesterol and increases beneficial plasma HDL-cholesterol and blood hematocrit in hypercholesterolemic humans. Waterleaf, compared to purslane, is an easier plant to grow, grows more efficiently and abundantly, has more aggressive growth characteristics, and has no known insect pests, thereby potentially serving a larger portion of the population. Waterleaf has higher levels of nutritionally-important vitamins (such as vitamin C, vitamin E, and Beta-carotene), minerals (such as calcium, potassium, and magnesium), and soluble fiber (pectin) than does purslane, all of which contribute to waterleaf's highly-elevated antioxidant values and its total biological effect. The combination in one plant species of n-3 fatty acids, antioxidants, and pectin that consequently has a positive and beneficial influence in reducing the risk of cardiovascular diseases in humans is a unique attribute of waterleaf that has not been shown to exist until the present invention.
The present inventors have designed food compositions comprising waterleaf and methods of reducing harmful blood cholesterols and simultaneously increasing beneficial blood cholesterols and vitamin and mineral levels using such food compositions and of treating and preventing coronary heart disease using such food compositions, all of which create potential for large-scale agricultural and biomedical utilization and applicability to a large segment of the population.